Light-induced conformational changes in full-length Arabidopsis thaliana cryptochrome.
Light-induced conformational changes in full-length Arabidopsis thaliana cryptochrome.
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DOI：
10.1016/j.jmb.2011.08.031
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发表时间：
2011-10-14
影响因子：
5.6
通讯作者：
Terazima M
中科院分区：
文献类型：
--
作者：
Kondoh M;Shiraishi C;Müller P;Ahmad M;Hitomi K;Getzoff ED;Terazima M
隐花色素（Cryptochromes，简称PHRs）是一类广泛分布的黄素蛋白，与光解酶（Photolyases，PHRs）具有同源性，光解酶是一类蓝光激活的DNA修复酶。与PHR不同，植物和动物的β都有一个C-末端结构域。该隐花色素C末端（CCT）结构域介导与其他蛋白质的相互作用，而PHR样结构域通过黄素腺嘌呤二核苷酸辅因子的还原和自由基形成将光能转化为信号。然而，PHR样结构域调节CCT结构域的机制尚不清楚。在这里，我们应用脉冲激光诱导的瞬态光栅法检测蓝光激发诱导的全长拟南芥隐花色素1（AtB 1）的构象变化。在光激发后观察到Atomic 1的扩散系数的显着降低，表明在这种单体蛋白中发生了大的构象变化。含有一个单一的突变（W324 F），废除了蛋白质内的电子传递级联的AtB 1没有表现出这种构象变化。此外，蛋白质的构象变化大大减少了CCT结构域缺乏。因此，我们得出结论，所观察到的大的构象变化所引发的光激发的PHR样结构域的C-末端结构域重排的结果。这种结构域间的调节对于蓝光信号转换为改变蛋白质-蛋白质相互作用以获得生物活性的能力至关重要。最后，我们证明了瞬态光栅技术提供了一个强大的方法，直接观察和了解感光体动力学。
Cryptochromes (CRYs) are widespread flavoproteins with homology to photolyases (PHRs), a class of blue-light-activated DNA repair enzymes. Unlike PHRs, both plant and animal CRYs have a C-terminal domain. This cryptochrome C-terminal (CCT) domain mediates interactions with other proteins, while the PHR-like domain converts light energy into a signal via reduction and radical formation of the flavin adenine dinucleotide cofactor. However, the mechanism by which the PHR-like domain regulates the CCT domain is not known. Here, we applied the pulsed-laser-induced transient grating method to detect conformational changes induced by blue-light excitation of full-length Arabidopsis thaliana cryptochrome 1 (AtCRY1). A significant reduction in the diffusion coefficient of AtCRY1 was observed upon photoexcitation, indicating that a large conformational change occurs in this monomeric protein. AtCRY1 containing a single mutation (W324F) that abolishes an intra-protein electron transfer cascade did not exhibit this conformational change. Moreover, the conformational change was much reduced in protein lacking the CCT domain. Thus, we conclude that the observed large conformational changes triggered by light excitation of the PHR-like domain result from C-terminal domain rearrangement. This interdomain modulation would be critical for CRYs’ ability to transduce a bluelight signal into altered protein–protein interactions for biological activity. Lastly, we demonstrate that the transient grating technique provides a powerful method for the direct observation and understanding of photoreceptor dynamics.
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影响因子：
16.6
作者：
Biskup, Till;Schleicher, Erik;Okafuji, Asako;Link, Gerhard;Hitomi, Kenichi;Getzoff, Elizabeth D.;Weber, Stefan
通讯作者：
Weber, Stefan
影响因子：
2.9
作者：
Harper, SM;Christie, JM;Gardner, KH
通讯作者：
Gardner, KH
影响因子：
--
作者：
Hara, T;Hirota, N;Terazima, M
通讯作者：
Terazima, M
影响因子：
3.4
作者：
Eitoku, Takeshi;Zarate, Xristo;Terazima, Masahide
通讯作者：
Terazima, Masahide
影响因子：
3.4
作者：
Hazra, Partha;Inoue, Keiichi;Terazima, Masahide
通讯作者：
Terazima, Masahide